In many industrial environments, such as for example in the case of the textile, printing, woodworking industries and in other environments, such as preservation cells for fruit and vegetables, as well as in storage areas for paper, wood, et cetera, it is necessary to control ambient humidity.
Enclosed spaces of this type are humidified but also cooled generally by using humidification systems which are constituted by pipes which are suspended from the ground and are connected to means for pumping water.
Nozzles are provided along said pipes and are designed to create a water aerosol which diffuses into the environment, humidifying the air.
To allow the air to absorb the water particles, their path of descent must be long enough.
The length of this path depends on the environmental parameters of the environment (humidity and temperature).
This path is typically parabolic, and therefore, during installation, in view of the ranges of the typical environmental parameters at which the system is to operate, it is necessary to calculate the correct height at which the pipes must be arranged so that the aerosol does not fall to the ground without being absorbed by the air, wetting the floor.
In some enclosed spaces, due to the limited height of the ceiling, it might not be possible to install the pipes at the optimum height, with evident problems regarding poor air humidification and the inevitable presence of water on the ground, at least in the presence of ranges of the environmental parameters.
In order to solve these problems, individual humidification modules are sometimes used which are connected to a common pumping system and are distributed in the appropriate regions of the enclosed space to be humidified.
These humidification modules are constituted generally by a duct which has an inlet for the water under pressure and an outlet constituted by one or more nozzles suitable to provide the aerosol.
Ventilation means of various kinds are provided behind the duct and are intended to create an air flow in a horizontal direction which is substantially parallel to the ejection axis of the nozzles, so as to strike the aerosol, extending the path of the water particles in a horizontal direction and consequently increasing their absorption in the air.
However, these modules, as well as systems of the traditional type in which the nozzles are arranged along simple pipes which are raised from the ground and are not associated with ventilation means, have the problem of dripping when the humidification system is stopped.
When the pumps that supply the water are stopped, the pressure in the pipes in fact does not drop instantly and therefore water at a pressure which is not sufficient to create a good aerosol tends to flow out of the nozzles (even if they are provided with valves which open at a minimum preset pressure level of the ejected stream, for example by means of a spherical flow control element associated with a suitably calibrated spring), introducing into the enclosed space water particles which are too heavy and cannot be absorbed even in the presence of an air stream which extends their path.